Nanomaterials towards Biosensing of Alzheimer’s Disease Biomarkers

Alzheimer's disease (AD) is an incurable and highly debilitating condition characterized by the progressive degeneration and/or death of nerve cells, which leads to manifestation of disabilities in cognitive functioning. In recent years, the development of biosensors for determination of AD's main biomarkers has made remarkable progress, particularly based on the tremendous advances in nanoscience and nanotechnology. The unique and outstanding properties of nanomaterials (such as graphene, carbon nanotubes, gold, silver and magnetic nanoparticles, polymers and quantum dots) have been contributing to enhance the electrochemical and optical behavior of transducers while offering a suitable matrix for the immobilization of biological recognition elements. Therefore, optical and electrochemical immuno- and DNA-biosensors with higher sensitivity, selectivity and longer stability have been reported. Nevertheless, strategies based on the detection of multiple analytes still need to be improved, as they will play a crucial role in minimizing misdiagnosis. This review aims to provide insights into the conjugation of nanomaterials with different transducers highlighting their crucial role in the construction of biosensors for detection of AD main biomarkers.This work was financially supported by: project UID/EQU/00511/2019—Laboratory for Process Engineering, Environment, Biotechnology and Energy—LEPABE and project UID/QUI/50006/2019—REQUIMTE, both funded by national funds through FCT/MCTES (PIDDAC); Project POCI-01-0145-FEDER-006939, funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; Project UID/EQU/00511/2019—Laboratory for Process Engineering, Environment, Biotechnology and Energy—LEPABE funded by national funds through FCT/MCTES (PIDDAC). The PhD grant of Pedro Carneiro (SFRH/BD/131755/2017) is financially supported by the Fundação para a Ciência e Tecnologia.info:eu-repo/semantics/publishedVersio

Trace metals in size-fractionated particulate matter in a Portuguese hospital: exposure risks assessment and comparisons with other countries

Hospitals are considered as a special and important type of indoor public place where air quality has significant impacts on potential health outcomes. Information on indoor air quality of these environments, concerning exposures to particulate matter (PM) and related toxicity, is limited though. This work aims to evaluate risks associated with inhalation exposure to ten toxic metals and chlorine (As, Ni, Cr, Cd, Pb, Mn, Se, Ba, Al, Si, and Cl) in coarse (PM2.5–10) and fine (PM2.5) particles in a Portuguese hospital in comparison with studies representative of other countries. Samples were collected during 1 month in one urban hospital; elemental PM characterization was determined by proton-induced X-ray emission. Noncarcinogenic and carcinogenic risks were assessed according to the methodology provided by the United States Environmental Protection Agency (USEPA; Region III Risk-Based Concentration Table) for three different age categories of hospital personnel (adults, >20, and 65 years). The estimated noncarcinogenic risks due to occupational inhalation exposure to PM2.5-bound metals ranged from 5.88×10−6 for Se (adults, 55–64 years) to 9.35×10−1 for As (adults, 20–24 years) with total noncarcinogenic risks (sum of all metals) above the safe level for all three age categories. As and Cl (the latter due to its high abundances) were the most important contributors (approximately 90 %) to noncarcinogenic risks. For PM2.5–10, noncarcinogenic risks of all metals were acceptable to all age groups. Concerning carcinogenic risks, for Ni and Pb, they were negligible (<1×10−6) in both PM fractions for all age groups of hospital personnel; potential risks were observed for As and Cr with values in PM2.5 exceeding (up to 62 and 5 times, respectively) USEPA guideline across all age groups; for PM2.5–10, increased excess risks of As and Cr were observed particularly for long-term exposures (adults, 55–64 years). Total carcinogenic risks highly (up to 67 times) exceeded the recommended level for all age groups, thus clearly showing that occupational exposure to metals in fine particles pose significant risks. If the extensive working hours of hospital medical staff were considered, the respective noncarcinogenic and carcinogenic risks were increased, the latter for PM2.5 exceeding the USEPA cumulative guideline of 10−4. For adult patients, the estimated noncarcinogenic and carcinogenic risks were approximately three times higher than for personnel, with particular concerns observed for children and adolescents

Traffic-Related Air Pollution: Legislation Versus Health and Environmental Effects

Ambient air quality is a very topical issue as it has an important influence on human health.Exposure to atmospheric pollutants may result in various adverse health effects. Theimpacts of air pollution are not confined only to human health but also to the environmentas a whole. In that regard, vehicular traffic emissions are especially important, because itsvolume is increasing every year. Consequently pollutants, such as nitrogen oxides (NOx),carbon monoxide (CO), particulate matter (PM), and polycyclic aromatic hydrocarbons(PAHs) are emitted into the atmosphere causing a significant decline of air quality acrossEurope, which results in hundreds of thousands of premature deaths every year. In order toimprove the situation, the European Union has been defining legislation on ambient airquality with limits of the respective pollutants and aiming to increase the levels of publichealth protection. Despite reductions in emissions, concentrations of these pollutants remainhigh often above existing targets exposing populations to levels that reduce lifeexpectancy, cause premature death and widespread aggravation to health.In this chapter, various aspects of air pollution are discussed with specific emphasis onvehicular road traffic. An overview of the current legislation related to air quality is given.The work then focuses on the health impacts of important traffic related pollutants, withparticular focus on polycyclic aromatic hydrocarbons (PAHs). The general description ofPAHs is presented with further discussion on their health and environmental impacts

Ultrafine Particles in Ambient Air of an Urban Area: Dose Implications for Elderly

Due to their detrimental effects on human health, the scientific interest in ultrafine particles (UFP) has been increasing, but available information is far from comprehensive. Compared to the remaining population, the elderly are potentially highly susceptible to the effects of outdoor air pollution. Thus, this study aimed to (1) determine the levels of outdoor pollutants in an urban area with emphasis on UFP concentrations and (2) estimate the respective dose rates of exposure for elderly populations. UFP were continuously measured over 3 weeks at 3 sites in north Portugal: 2 urban (U1 and U2) and 1 rural used as reference (R1). Meteorological parameters and outdoor pollutants including particulate matter (PM10), ozone (O3), nitric oxide (NO), and nitrogen dioxide (NO2) were also measured. The dose rates of inhalation exposure to UFP were estimated for three different elderly age categories: 64–70, 71–80, and >81 years. Over the sampling period levels of PM10, O3 and NO2 were in compliance with European legislation. Mean UFP were 1.7 × 104 and 1.2 × 104 particles/cm3 at U1 and U2, respectively, whereas at rural site levels were 20–70% lower (mean of 1 ×104 particles/cm3). Vehicular traffic and local emissions were the predominant identified sources of UFP at urban sites. In addition, results of correlation analysis showed that UFP were meteorologically dependent. Exposure dose rates were 1.2- to 1.4-fold higher at urban than reference sites with the highest levels noted for adults at 71–80 yr, attributed mainly to higher inhalation rates

Indoor air quality in health clubs: Impact of occupancy and type of performed activities on exposure levels

Associations between indoor air quality (IAQ) and health in sport practise environments are not well understood due to limited knowledge of magnitude of inhaled pollutants. Thus, this study assessed IAQ in four health clubs (HC1-HC4) and estimated inhaled doses during different types of activities. Gaseous (TVOCs, CO, O3, CO2) and particulate pollutants (PM1, PM4) were continuously collected during 40 days. IAQ was influenced both by human occupancy and the intensity of the performed exercises. Levels of all pollutants were higher when clubs were occupied (p < 0.05) than for vacant periods, with higher medians in main workout areas rather than in spaces/studios for group activities. In all spaces, TVOCs highly exceeded legislative limit (600 μg/m3), even when unoccupied, indicating possible risks for the respective occupants. CO2 levels were well correlated with relative humidity (rs 0.534-0.625) and occupancy due to human exhalation and perspiration during exercising. Clubs with natural ventilations exhibited twice higher PM, with PM1 accounting for 93-96% of PM4; both PM were highly correlated (rs 0.936-0.995) and originated from the same sources. Finally, cardio classes resulted in higher inhalation doses than other types of exercising (1.7-2.6).This work was supported by European Union (FEDER funds through COMPETE) and National Funds (Fundação para a Ciência e Tecnologia) through projects UID/QUI/50006/2013 and UID/EQU/00511/2013-LEPABE, by FCT/MEC with national funds and co-funded by FEDER in the scope of the P2020 Partnership Agreement. Additional financial support was provided by FCT through fellowship SFRH/BPD/105100/2014.info:eu-repo/semantics/publishedVersio

Environmental Particulate Matter Levels during 2017 Large Forest Fires and Megafires in the Center Region of Portugal: A Public Health Concern?

This work characterizes the dimension and the exceptionality of 2017 large- and mega-fires that occurred in the center region of Portugal through the assessment of their impact on the ambient levels of particulate matter (PM10 and PM2.5), retrieved from local monitoring stations, and the associated public health risks. PM10 and PM2.5 concentrations were increased during the occurrence of large fires and megafires, with daily concentrations exceeding the European/national guidelines in 7–14 and 1–12 days of 2017 (up to 704 µg/m3 for PM10 and 46 µg/m3 for PM2.5), respectively. PM10 concentrations were correlated with total burned area (0.500 0.05) and with monthly total burned area/distance2 (0.500 0.05). The forest fires of 2017 took the life of 112 citizens. A total of 474 cases of hospital admissions due to cardiovascular diseases and 3524 cases of asthma incidence symptoms per 100,000 individuals at risk were assessed due to exposure to 2017 forest fires. Real-time and in situ PM methodologies should be combined with protection action plans to reduce public health risks. Portuguese rural stations should monitor other health-relevant pollutants (e.g., carbon monoxide and volatile organic compounds) released from wildfires to allow performing more robust and comprehensive measurements that will allow a better assessment of the potential health risks for the exposed populations.This work was financially supported by European Union (FEDER funds through COMPETE) and National Funds (Fundação para a Ciência e Tecnologia) [projects UIDB/50006/2020, UID/EQU/00511/2013-LEPABE], by the FCT/MEC with national funds and cofounded by FEDER in the scope of the P2020 Partnership Agreement. This study was also supported by the project “PCIF/SSO/0017/2018- A panel of (bio)markers for the surveillance of firefighter’s health and safety”, funded by Portuguese National Funds through FCT—Fundação para a Ciência e Tecnologia. M. Oliveira thanks to FCT/MCTES for the CEEC-Individual 2017 Program Contract [CEECIND/03666/2017].info:eu-repo/semantics/publishedVersio

(Ultra) Fine particle concentrations and exposure in different indoor and outdoor microenvironments during physical exercising

Although regular exercise improves overall well-being, increased physical activity results in enhanced breathing which consequently leads to elevated exposure to a variety of air pollutants producing adverse effects. It is well-known that one of these ambient air contaminants is ultrafine particles (UFP). Thus, this study aimed to (1) examine exposure to particle number concentrations (PNC) in size ranging from N20-1000 nm in different sport environments and (2) estimate the respective inhalation doses across varying activity scenarios based upon the World Health Organization recommendations for physical activity. PNC were continuously monitored (TSI P-Trak™ condensation particle counter) outdoors (Out1-Out2) and indoors (Ind1-Ind2; fitness clubs) over 4 weeks. Outdoor PNC (total median 12 563 # cm-3; means of 20 367 # cm-3 at Out1 and 7 122 # cm-3 at Out2) were approximately 1.6-fold higher than indoors (total median 7 653 # cm-3; means of 11 861 # cm-3 at Ind1 and 14 200 # cm-3 at Ind2). The lowest doses were inhaled during holistic group classes (7.91 × 107-1.87 × 108 # per kg body weight) whereas exercising with mixed cardio and strength training led to approximately 1.8-fold higher levels. In order to optimize the health benefit of exercises, environmental characteristics of the locations at which physical activities are conducted need to be considered.This work was financially supported by project UID/EQU/00511/2019 - Laboratory for Process Engineering Environment, Biotechnology and Energy–LEPABE and project UID/QUI/50006/2019 - Associate Laboratory Research Unit for Green Chemistry - Technologies and Processes Clean–LAQV, funded by national funds throughFCT/MCTES (PIDDAC).info:eu-repo/semantics/publishedVersio